Improvement in machines for cutting wood-screws



UNITED STATES PATENT Errori.

FARVELIJ H. HAMILTON, OF SOHENEO'IADY, NEV YORK.

IMPROVEMENT lN MACHINES FOR CUTTING WOODMSGREWS.

Specification forming part of Letters Patent No. ELIGE, dated July 8,i841.

T0 @ZZ whom it may concern:

Beit known that I, FARWELL H. HAMIL- TON, of the city and county ofSchenectady and State of New York, have invented a new and ImprovedMachine for Outting'the Threads on food-Screws; and I do hereby declarethat the following is a full and exact description.

The nature of my invention consists in mak` ing a double self-operatingmachine of simple construction, and in making my dies of suchconstruction that they cut very fast and easy, and also in giving to theoil-tube its requisite motion by a simple arrangement of machinery.

Io enable others skilled in the art to make and use my invention, IwillA proceed to describe its construction and operation.

I place my spindles (marked a in the drawings) in their proper stands orframes, about fourteen inches apart, parallel with each other, on eachof which spindles, near the back end, I place a pinion, b, of about twoinches diame` te'r, and which has two or three inches length of cog,according to the length of the screws to be cut. Between these twopinions I place a cog-wheel, c, of about twelve inches diameter, whichmatches into the left-hand pinion I) of Fig. l, and on the right-handunder pinion b I place another pinion, (see d, Fig. 2,) which matchesinto I) and c, thereby giving opposite and alternate rotary motion tothe spindles. The shaft ofthe wheel c extends far enough back to receiveanother pinion, which matches into the rack at E', whence it derives itsmotion. On the front end of each spindle I place a round casting ofabout three inches diameter, (marked f,) across the face of which I cuta dovetailed groove, in which the dies 7L h are placed. (See Fig. 6,)For larger screws I sometimes make a square groove and pnt on a thinplate of iron to keep the dies in place, as in Fig. 7. About two inchesback offis another casting, g, on the front end of which is a ange orprojection, through a slot in which I pass two springs, I I. Thesesprings are fastened by a screw at i i', and thev other ends rest on theends of the dies at 7a, Fig. 1. Through the flange, and extending intothe slots, I put a screw, 7.x, Fig. I, by means of which the springs aremade to press more or less on the dies7 as occasion requires.Immediately behind the dies in the castingf, under each spring, I put ascrew, (see A, Fig. 1,) to

prevent the dies from being pressed down farther than is necessary tocut a full thread.

The spindles are made to traverse back and forward, and the dies forcedon the blank to be cut away byashell-thread or endless screw and aclasp.V (Marked L in Fig. 2.) \Voodscrews before the threads are cut onthem are termed blanks7 On the circular horizontal plates, (marked M,)which I term dial plates,7 I fix two or more vises, which hold theblanks while in the process of being cut. The blanks are fastened intothe vises by means of a pin made fast into the dial-plate and passingthrough the vise,with a nut on the top,which is turned by a crankwrench. (See N, Fig. 3.) The blanks are held by the head, the viseshaving a nick in the jaws for that purpose. The jaws of the vise aremade to open by means of a spiral spring around the vise-pin. Thedialplate turns on its axis, so that when one blank orscrew is cuttingthose in the other vises may be changed. The dial-plates are held fastby springs O O, Fig. 3, and a nick in the rim of the dialplate on thcunder side, the end of the spring turning up to tit into the nick.

At S, Figs. 2 and 3, is represented a rod and twisted wire, which isused to press down the spring when the dialplates are to be turned.

AtTis represented a tube to contain oil, of proper length to extend toeither blank when in position to be cut. Into each end of this tube Iinsert a piece of lamp-wick,which prevents the oil from dropping, butwhich is suficiently saturated with oil to oil the screws alternately ateach end when the spindle is run back. To give the oiltube motion, Imake a collar of one and a half inch diameter, into which I turn agroove about one quarter of an inch deep and wide, and I put this collaronto one of the spindles just behind the thread. I then make anelbow,which hangs on a pivot at its angle U, Fig. l, one end of whichhas a fork with rounded ends and turned inward, so that it may run inthe groove of the collar at o, Fig. l. The fork and collar arerepresented by Fig. 5. The other end of the elbow extends forward towardthe oil-tube, and is bent down about one inch and a half, as representedat x, Fig. 2. On the stand of the oil-tube I put a band, a, Fig. 3, witha pin extending back about one and one-half inch. On this pin,

near its extremity, I put a vertical rod about four inches long andthree-quarters of an inch wide, (see rw, Fig. 2,) working on its center,and made thick or with a hub in the middle, so that it may work true. Inthelower end of this rod I put the forward end of the elbow at x. Iplace the shaft e, Fig. 2,which holds the oil-tube, in a slantingposition, or at an angle of twenty or thirty degrees, so as to give theoil-tube a slanting instead of a perpendicular movement. This shaftissupported by collars rmly attached to the stand. On the back end of thisshaft I put a nut with ahandle or pin, z, Fig. 2, the pin being bent soas to hang perpendicularly, and having a thread on it. On this pin I putanother and similar nut and pin, g/,which pin extends back and enters aslot in the upper end of the said rod,(marked w,) and thus a connectionis formed from the oil-tube to the collar on the spindle. The spindletraversing back and forward gives the requisite motion to the oil-tube.By moving the nut and pin y up and down more or less movement is givento the oil-tube.

In making the dies, after Iitting them to their grooves, I make a nickin the end (see a, Fig. 9) about one and one-fourth of an inch deep, andthe width is according to the size of the screw I Wish to cutthat is,it' the blank is one-fourth of an inch in diameter which I wish to cut,I make the nick oneeighth of an inch wide, or so as to make the threaddeep enough without having the dies come together. I then ile it offeach way from the nick-beveling, (see u, Fig. 9,) except a thin lip atthe front side, e, Fig. 9. This lip is left to enable the dies to run onthe screw or blank more easily, and in which to make a countersink. Ithen put the dies in their grooves and run in a tap about the size ofthe screw I wish to cut,

which, instead of a thread only, makes teeth in the sharp corners. (Seet' i, Fig. 9.)

Figs. 8 and l0 represent the ends of the dies after they are finished-8a bevel and 10 a square die.

The dies generally used have a regular thread similar to those used forcutting bolts. Mine have the thread all tiled away, leaving sharp pointsonly. Mine will cut more easilyand faster than any of the other kindsnow in use. The novelty and superior advantages of mine consist in theforegoing particulars, and also in that they cut the iron out clean andleave the thread and interstices perfectly smooth, while the others bypartially pressing the iron out have the effect to raise the thread,make the screw longer, and leave it rough and nneven.

This machine may be applied to the cutting of any kind of iron or brassscrews, and may be moved by any of the different kinds ofcrank oreccentric motion.

What I claim as my invention, and desire to secure by Letters Patent,is-

1. The arrangement of machinery which operates the oil-tube, and itscombination with the machinery which gives to the spindles an oppositeand alternate rotary mot-ion, in the manner and for the purposedescribed.

2. The method herein described of making the cutting part of the dieswith teeth instead of a thread, in combination with the lips, as abovedescribed.

This difference in the construction of the dies from all others givesthem the superiority and advantages above enumerated.

FARWELL H. HAMILTON.

Witnesses:

G. F. YATEs, WM. B. Pinnen.

